WWII US staff car. These should be olive drab in combat zones, but glossy olive for US Army, and glossy gray for US Navy in the United States. Painted in glossy black they would probably work as a car to transport FDR or President Truman.
https://fidelismodels.com/collections/3d-filament-fighters-models/products/cadillac-series-75-staff-car
Cadillac staff car used for high ranking officers in World War Two. They were actually very common in Europe after the Normandy invasion, with olive drab paint jobs and full tactical markings.
This is a 3d printed Filament Fighters model sold by Fidelis Models in HO 1/87th scale.
I have about 50 Filament Fighters models and generally I like them a lot. This particular one comes in a front and rear half. It requires a little bit of sanding to make the roof as smooth as I like but it's not very time consuming. I have one so far but I am sure I will get more of the staff car.